Genetha Campbell carries free water being distributed at the Lincoln Park United Methodist Church in Flint. (Paul Sancya / AP)

The FBI is the latest law enforcement agency to join the investigation into the Flint water crisis, according to news reports. The crisis is also being investigated by the U.S. Department of Justice and the Michigan Attorney General’s office.

According to NBC News, the Detroit U.S. Attorney’s office confirmed the FBI was a part of a multi-agency team investigating the Flint situation. The team also includes the U.S. Postal Inspection Service and the Environmental Protection Agency Criminal Investigation Division.

The city of Flint is currently dealing with a “man-made” disaster after a decision to switch from the Detroit water system to the polluted Flint River left local residents with brown, foul-smelling water. The decision was made by emergency managers appointed by Michigan Gov. Rick Snyder. The water, which was contaminated with lead, also caused rashes and has been linked with diminished academic performance and behavioral issues in children.

The federal agencies will look into whether criminal charges needed to be filed in the case. And they may find plenty of evidence. News reports say Snyder was made aware of the contaminated water last spring, but his staffers dismissed Flint residents’ complaints. Snyder has released 274 pages of emails linked to the water crisis. The emails, which are heavily redacted, reveal Snyder staffers called Flint residents who complained about contaminated water the “anti-everything group.”

An email revealed that in January 2015, workers at the Michigan Department of Technology, Management & Budget’s Flint office were ordered to only drink bottled water. According to another email, when a mother complained about the effects of lead poisoning, a nurse told her, “It is just a few IQ points. … It is not the end of the world.”

In a New York Times video, Michael Pitt, an attorney for a Flint resident who has filed a lawsuit against Snyder, accused the government of trying to cover up the crisis.

“They were staring at a public health emergency and they sat on it,” Pitt said.

State officials finally admitted there was a problem with the water in the last part of 2015.

NBC News reports that two Michigan Department of Environmental Quality workers have been suspended and a U.S. Environmental Protection Agency employee has resigned over the Flint water crisis.

Snyder is now facing massive demonstrations and calls for his resignation and arrest.

Filmmaker Michael Moore, a native of Flint, has started a petition calling for Snyder’s incarceration. He recently posed with a pair of handcuffs and a sign bearing the hashtag #ArrestGovSnyder. The petition currently has more than 450,000 signatures.

“They [Flint residents] deserved more than to be poisoned by their own governor — a governor who thought that, because the people in the town were politically weak, he could get away with this unnoticed and without a fight. He figured wrong,” Moore said.